This invention relates to a method and apparatus for introducing a fluid into a closed system.
Introduction of a fluid into a closed system can require devices and techniques to be developed that optimize the neatness and cleanliness of the introduction. The introduction of a fluid can be particularly challenging when the fluid has a color, odor, or is potentially dangerous. One type of fluid and system for which these issues can be important is in leak detection methods developed to analyze fluid systems, such as climate control systems, such as heating, cooling, ventilating, and air conditioning systems, using dyes. Some methods employ emissive substances, such as, for example, fluorescent or phosphorescent dyes that are added to the refrigerants and/or lubricants of a climate control system. Suitable leak detection dyes include naphalimide, perylene, thioxanthane, coumarin, or fluorescein and derivatives thereof. Leaks can be detected by observing light emission from the dye at leak sites resulting from excitation of the dye with a light source having particular illumination characteristics (e.g. at wavelengths suitable to excite the dye and cause light emission from the dye). In general the dyes emit brightly when excited by light in the 190 to 700 nanometer wavelength range.
In general, the invention features an apparatus and method for introducing a fluid, such as a leak detection dye composition, into a closed system, such as a climate control system. The apparatus can include a body with two ports. One port attaches to a service port of the closed system and the other port holds a fluid containing reservoir used to transfer the fluid into the system. The two ports can be directly in-line with one another or the second port can be offset by an angle in the middle of the body. This offset can allow for complete draining of the fluid into the system when the system port connection with the first port of the apparatus is horizontal.
In one aspect, an apparatus for introducing fluid into a system includes a body, and a supply member adjacent to the first port extending into the body. The body includes an interior region within the body, a first port adjacent to the interior region, and a second port fluidly connected to the first port by a passageway within the body. The supply member includes a valve actuating end adjacent to the first port and a fluid supply end adjacent to the second port. The supply member is in moveable contact with the valve actuating end such that the fluid supply end moves toward the interior region when the valve actuating end moves away from the interior region, and the fluid supply end moves away from the interior region when the valve actuating end moves toward the interior region. The body can include a gasket adjacent to the first port.
In another aspect, an apparatus for introducing a leak detection dye composition into a climate control system includes a body, a first supply member adjacent to the first port and extending into the body, and a service port connector adjacent to the first port. The body includes an inner region within the body, a first port adjacent to the interior region, and a second port fluidly connected to the first port by a passageway within the body. The first supply member includes a valve actuating end adjacent to the first port and a contact end within the body, and a second supply member adjacent to the second port and extending into the body. The second supply member includes a valve actuating end adjacent to the second port, the second supply member being in moveable contact with the contact end of a first supply member such that the second supply member moves toward the interior region when the first supply member moves away from the interior region and the second supply member moves away from the interior region when the first supply member moves toward the interior region.
The apparatus can include a service port connector adjacent to the first port. The service port connector can include a latch mechanism adjacent to the first port. The latch mechanism can include a release sleeve including a plurality of balls. In another embodiment, the service port connector can include a swivel nut adjacent to the first port and having threads on an external surface of the nut configured to threadably attach to a surface of a service port. The apparatus can include a fluid supply connector adjacent to the second port. The fluid supply connector can include threads configured to threadably receive a threaded fluid supply container. The apparatus can include a spring within the body and adjacent to the supply member, or the first supply member, to bias the valve actuating end toward the interior region.
The supply member can include a first supply member including the valve actuating end and a second supply member including the fluid supply end and in moveable contact with the first supply member. The first supply member and the second supply member can surround the passageway.
In another aspect, a method of introducing a fluid into a closed system includes attaching a first port of an injection apparatus to a service port of the system, attaching a fluid supply reservoir to a second port of the injection apparatus, moving the fluid supply reservoir relative to the injection apparatus to actuate a valve in the fluid supply reservoir and a valve in the service port, and transporting a fluid from the fluid supply source though the injection apparatus and into the fluid system. The fluid supply reservoir can be a container including a leak detection dye composition. The container can be a pressurized container including a threaded neck including a valve. The leak detection dye composition can include a refrigerant and a dye and, optionally, a lubricant. The first port can be attached to the service port by sealably coupling the first port to the service port. The fluid supply reservoir can be attached to the second port by threading the supply reservoir into the second port. The fluid supply reservoir can be moved relative to the injection apparatus by contacting the supply reservoir with a supply member within the injection apparatus and sliding the supply member toward the service port to actuate the valve in the service port. The fluid can be transported by propelling the fluid from the fluid supply reservoir into the fluid system with a refrigerant.
In another aspect, a method of introducing a leak detection dye composition into climate control system includes providing an apparatus, attaching a service port of the climate control system to a first port of the apparatus, inserting a container including a leak detection dye composition into a second port of the apparatus, moving the container toward the fluid supply end of the apparatus, moving a supply member and a valve actuating end of the apparatus toward the service port thereby opening the service port, and transporting the leak detection dye composition from the container to the climate control system. The container can be moved toward the fluid supply end and the supply member and the valve actuating end can be moved toward the service port substantially simultaneously. The leak detection dye composition can be transported by propelling the leak detection dye composition from the container into the fluid system with a refrigerant. The method can include opening a valve in the container with the fluid supply end after opening the service port or moving the supply member and the valve actuating end away from the service port thereby closing the service port and removing the apparatus from the service port.
The apparatus can be connected to the service port of a climate control system. This connection can be effected using a swivel nut as part of the body that has external threads matching the internal threads of the service port. The threads can be 8 or 9 mm threads. Alternatively, the connection to the service port of the climate control system can be made using a latch mechanism. This latch mechanism could be made up of a ball release sleeve and latch balls that fit into a groove on the service port. Other forms of connection to the port known to those skilled in the art are also possible. An important aspect of the apparatus is that connection to the service port forms a sealed connection with a gasket adjacent to the first port on the apparatus.
The method and apparatus can be used for leak detection in a climate control system. The climate control system can be a mobile, stationary, window air conditioning system such as an automotive, portable, residential, or commercial air conditioning system or any other hermetic system that employs a refrigerant and a lubricant.
The fluid containing container can be connected to the second port via threads on the container and on an inner surface of the second port. The container can be pressurized and can include a valve. The container can be configured to form a seal with the second port to minimize spillage of the fluid. Similarly the first port can be configured with a gasket to form a seal with the service port of the system. When fluid is introduced into the system, the container is oriented to allow the fluid to flow by gravity to the valve. The remaining volume in the container contains a propellant, which can be a gas at atmospheric pressure and ambient temperature, in an amount sufficient to transport substantially all of the fluid from the container into the system.
The leak detection dye composition container can be a pressurized canister including a valve and threaded connector and sealing mechanism. The leak detection dye composition can include a dye, a refrigerant, and, optionally, a lubricant. The leak detection dye composition container can have a volume of less than about 5 ounces, preferably less than about 4 ounces and more preferably less than about 3 ounces. For example, the canister volume can be between 2 and 2.5 ounces. The dye composition can be added to the system by connecting the body to the service port, threading the dye composition container onto the second port causing the supply member to move into the body, and forcing the supply member into the service port to open a valve in the port. Once the container is threaded far enough onto the second port, the container valve will be actuated to open the container. Pressurized material in the container, such as refrigerant or other propellant, expels the dye composition from the container into the system.
Advantageously, the method and apparatus can allow fluid to be added cleanly, with mimimal or reduced spillage, to the closed system, and to minimize or reduce spillage of fluid when the apparatus is removed from the service port. By minimizing the volume and wetted surface area of the interior of the body of the apparatus, and by ensuring that there is an excess of propellant to blow the fluid through the body, the method and apparatus reduces the possible spillage of fluid. In addition, by including a biasing spring on the supply member in the body, the apparatus can be cleanly removed from the service port because the service port can be closed before the apparatus is removed from the service port. Finally, the angled nature of the apparatus ensures that the container or reservoir can be oriented so that substantially all of the fluid is removed from the container or reservoir and transported into the system.
The details of one or more embodiments invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.